Fitting for wire rope and strands



Dec. 16, 1952 w J GlLMORE 2,621,385

FITTING FOR WIRE ROPE AND STRANDS Filed Dec. 15. 1947 ATTORNEY PatentedDec. 16, 1952 FITTING FOR WIRE ROPE AND STRANDS William J. Gilmore,Adrian, Mich, assignor to American Chain & Cable Company, Inc.,Bridgeport, Conn., a corporation of New York Application December 15,1947, Serial No. 791,777

1 Claim. 1

This invention relates to fittings for wire rope and strands.

Fittings on ferrous rope or strand are advantageously made in the formof sleeves which are swaged or cold worked onto the rope thus avoidingexcessive heat which would damage the rope. However, as a commercialpractice, they are very difiicult to apply with the assurance that thehold will be sufiicient if they are subjected to a stress sufiicient tobreak the rope.

It is therefore a primary object of the present invention to provide afitting which can be applied on a commercial production basis to developthe full strength of the rope or strand to which it is applied.

Referring now to the drawings:

Fig. 1 is a view showing a cylindrical blank before the first operationthereon;

Fig. 2 shows a similar blank with indentations formed therein as apreliminary step to the fabrication of the fitting, and with alongitudinal hole drilled therethrough;

Fig. 3 is a section taken on line 3-3 of Fig. 2;

Fig. 4 is a view of the fitting after assembly around the strand andafter completion of the swaging operation;

Figs. 5, 6 and '7 are sections on lines 5--5, 6-6, and respectively ofFig. 4; and

Fig. 8 is a view of a modified blank used in the practice of thisinvention.

This invention is described in connection with ferrous strand, for easeof description, and because it is particularly well adapted to strand.It has always been diflicult to grip strand tightly enough, and thefailures occur as slippage of the fitting on the wire, rather than asbreaking of the wire. However, it is to be understood that the inventionis not limited to strand, but can be applied to rope and cable withequal facility.

The example shown is a plain cylindrical fitting, utilized as an ending.As a preliminary step, a solid cylindrical piece of metal l0, preferablywith a frustro-conical end II is pressed or punched so as to produce theexterior contour shown in Figs. 2 and 3. This embossing consists ofimpressing in the cylindrical surface a series of depressions l2 shownas being segments of cylindrical surfaces. It will be noted that theyoccur in pairs, each succeeding pair being spaced 90 around theperiphery of the blank, and all preferably equally spaced from eachother. The making of these depressions throws the metal of the blankinto a sort of flattened indented shape, as best seen in Figure 3.

After the exterior of the blank has been deformed as above described, abore I3 is formed therethrough, which may be cylindrical, but preferablyhas a tapered bell mouth at |4,'the bore being sufficiently large toreceive the strand to be secured therein.

A strand [5 is inserted in the bore, and the entire fitting, or at leastas much of it as surrounds the strand, is then subject to cold workingby swaging, so that it becomes cylindrical. The depressions in thesurface are substantially obliterated, and the strand is tightly held bysuch swaging.

The most important feature of this invention is the arrangement of thedepressions and the resultant deformation of the strand under swaging.As shown in Figures 4 to 7 inclusive, the swaging results in adeformation of the strand, by actual displacement of the wires thereof,so that it takes on an oval cross-section directly under each pair ofdepressions. However, the next adjacent pair of depressions, which isaround the periphery of the blank, results in an oval the major axis ofwhich is disposed at right angles to the axis of the first-mentionedoval.

As the wire of which the strand is made is relatively stifi and hard,the deformation is sufiicient to render it impossible to pull the strandout of the fitting. There is considerable friction opposing suchwithdrawal, but it can be inferred that the development of the fullstrength of the joint depends upon the rapid change from one oval toanother along the axis of the fitting.

This inference is justified by the entire absence of slippage beforefailure, in testing, as distinguished from swaged fittings without thedepressions. This inference is also supported by the fact that thedegree of swaging is not overly critical. There is one feature of thisinvention which is not inherent in the construction, but neverthelessimportant in the shown structure. As can be seen in Figs. 5 and 6, thematerial of the sleeve is thickest across the minor axis of the oval.This is as it should be, as the metal is amply strong in tension, andwill not rupture in region A as an attempt is made to pull the strandout. Furthermore, the thick Section B cannot bend, which prevents thesleeve from distorting in such a manner as to permit the strand to takea more circular form. Such distortion would, of course, if permitted,tend to result in slippage. This construction is in distinction tosleeves having a uniform thickness around a non-circular strand, whichmust be made thicker all around to prevent such distortion, and are thusheavier than is theoretically necessary.

Instead of swaging the depressions l2 into the blank, it is perfectlyfeasible to machine them. As an example, in Fig. 8 a blank I8 is shownwith arcuate slots [9 milled across the cylindrical surface, to servethe same function as the deformation practiced in the structure shown inthe other views. There are possibly other types of blanks which can be:used, depending on the desired result, and it. is therefore to beunderstood that the above constructions are illustrative and notlimitative, and that the scope of the present invention is to bedetermined from the appended claim.

I claim:

An article of manufacture comprising a. ferrous stranded structure and asleeve compacted thereon, said sleeve having a substantially cylindricalsurface, the bore of the sleeve and the portion of the strandedstructure therein having oval cross-sections at spaced points along thelength, the major axis of the oval cross-section at one point. being. atsubstantially right. angles,

to the. major axis of the oval cross-section at the other point thetransition from one oval cross-section to the other being, in thenatureof a widening to a substantially circular cross-section and flatteningto the other oval cross-section.

WILLIAM J. GILMORE.

REFERENCES CITED The following references are of record in the file ofth'm patent:

UNITED STATES PATENTS Number Name Date 557,037 Toquet Mar. 24, 1896650,860 McTighe June 5, 1900 650,862 McTighe June 5, 1900 947,601Schmidmer Jan. 25, 1910 1,711,832 Cooper May 7, 1929 2,008,227 ReillyJuly 16, 1935 2,109,837 Davis Mar. 1, 1938 2,247,928 Temple July 1, 194120 2,276,140 Andren Mar. 10, 1942 FOREIGN PATENTS Number Country Date528,376 Germany Mar, 25, 1930'

